Context modulates figurative language deficits

Context critically guides language comprehension. For figurative language, context can increase the salience of non-literal interpretations and decrease the cognitive effort needed to derive them. In everyday use, figurative expressions are almost always embedded in a narrative context, be it a story, article or conversation. However, most studies on figurative language use minimal contexts like word pairs or individual decontextualized sentences. Moreover, some types of figurative language may rely on context more than others to be understood. Our goal was to test 1) whether comprehension deficits in patients with metaphor impairments are improved with context, and 2) whether metaphor impairments are dissociable from deficits in another form of figurative language – irony. To address these questions, we developed short vignettes and comprehension questions for four different conditions (literal, metaphor, simple irony and metaphorical irony) that were matched across conditions in accuracy and response times among control participants. Four focal lesion patients with metaphor deficits of different types and severity based on a single sentence comprehension task, showed distinct patterns when tested with vignettes. A patient with a mild impairment now showed none. Two patients with robust, selective deficits in metaphor comprehension responded oppositely: one patient’s comprehension was no longer impaired, while the other’s worsened. The fourth patient’s pattern of impairment remained unchanged. No patients demonstrated impaired simple irony comprehension, but two showed impaired understanding of metaphorical-ironies. We conclude that metaphor and irony impairments are dissociable, and patients vary in whether they benefit from context.